It is an object of the present invention to provide a composition for generating a particulate-free, non-toxic, non-flammable, odorless and colorless gas for use in various environments, primarily for the inflation of an air bag in an automotive vehicle. However, the composition of this invention may also be employed to inflate such items as an inflatable raft or a passenger escape chute of an airplane.
The unique advantage of employing the formulations of the instant invention resides in the cycling and/or the ballistics of the composition. Whereas prior art composition grains consisting essentially of a fuel, e.g., GN, and an oxidizer, e.g., KP, do not maintain their size during 200 cycles at -40 to .+-.107.degree. C. and 17 days at 107.degree. C., the instant formulations, containing AGN, KN and PVA with GN and KP exhibit no significant change in diameter or in strength during said tests. Likewise, in contrast to compositions described in the prior art, the inventive formulations consisting essentially of GN, KP and AGN, exhibit materially higher burning rates, in ips (inches per second), at 2000 and at 4000 psi.
To utilize the generated gas requires the provision of an enclosed pressure chamber having at least one exit port and a composition in the form of a powder charge or pressed into propellant grains of a suitable shape, located within said compression chamber. The described composition comprises a propellent containing a guanidine nitrate and an aminoguanidine nitrate mixed with potassium perchlorate, and optionally potassium nitrate, as oxidizers and, optionally, a polyvinyl alcohol binder. The formulation is prepared by forming a solid solution comprised of GN, AGN, KN and PVA, which in turn is blended with KP powder; said composition is used in the disclosed pressure chamber having at least one exit port. Thus, upon ignition, the formulation, in response to a sudden deceleration being detected by a sensor device in the pressure chamber substantially instantly generates a gas and conducts it through the exit ports of said pressure chamber to accomplish a desired function, such as inflating an automotive vehicle air bag.